1. Technical Field
The present disclosure relates to suture anchors and, more particularly, to self-tapping screw type suture anchors and methods of use.
2. Background of Related Art
During surgery it is often necessary to attach prosthetic implants or soft tissue such as muscle tissue, ligaments, or tendons to hard tissue such as bone. Various types of surgical fasteners are employed for accomplishing this function, including staples, screw and washer systems, suture anchoring devices, and tissue anchors.
The first of these types is illustrated in U.S. Pat. Nos. 4,454,875 and 4,570,623, which show metal staples with spikes on the underside of the crosspiece to secure ligaments.
Fasteners included in the second of these types are available as screw-washer combinations wherein the screw is fabricated from a surgically suitable metal, such as titanium or stainless steel alloy, and is usually of self-tapping design. Suture anchors are adapted to be inserted into predrilled holes in bone and can be made of bioabsorbable material. When securing a ligament or suture within a bore drilled in bone, the self tapping screws may abrade the ligament or suture if the ligament or suture is positioned adjacent the screw within the bore as the screw is threaded into the bone.
Suture anchors are also used to draw tissue adjacent bone. The anchor, having a first end and a suture fixedly attached thereto, is anchored in bone and a second end of the suture is threaded through tissue and a knot is tied to secure the tissue to bone.
What is needed is a suture screw capable of freely receiving lengths of suture material therein so as to draw tissue adjacent bone and/or provide the ability to add or substitute suture material after the suture screw has been positioned within the bone.